A method for preparing hexamethylcyclotrisiloxane was described by Winton Patnode and Donald F. Wilcok in The Journal of the American Chemical Society, Vol. 68 (1946), pages 360-361, in which high molecular weight dimethylpolysiloxanes were heated to a temperature of from 350.degree. to 400.degree. C. The resultant condensate contained 44 percent [(CH.sub.3).sub.2 SiO].sub.3, 24 percent [(CH.sub.3).sub.2 SiO].sub.4, 9 percent [(CH.sub.3).sub.2 SiO].sub.5, 10 percent [(CH.sub.3).sub.2 SiO].sub.6 and 13 volume percent above hexamer.
Although hexamethylcyclotrisiloxane could be prepared by this method, the yield of cyclic trisiloxanes was so low that the method was not practical on a commercial scale.
Therefore, it is an object of the present invention to provide a method for preparing cyclic dimethylpolysiloxanes. Another object of this invention is to provide an improved method for preparing hexamethylcyclotrisiloxanes. Still another object of this invention is to provide an improved method for preparing higher yields of hexamethylcyclotrisiloxanes. A further object of the present invention is to provide a room air deodorizer composition containing hexamethylcyclotrisiloxane as a carrier for a fragrance substance.